"My great-grandmother’s dog had puppies one month after my 1st birthday and my parents got the fattest puppy and named him Polar Bear. We were best friends up until his last day. (Picture on the left: Me at age 1 when Polar was a month old. Picture on right: Me at age 17 years old when Polar was 16 years old)" – alyssad4c6746f0a

"The first picture is from 2011 when I first met Lexie my labradoodle (I was 13, she was two weeks old). The middle two are from last year, and the last one was taken this year, when I’m now 20 and she’s 7." – gingerwarrior13

"The first pictures is a bit after Christmas when we got her and she started hitting the pre-teen puppy days. The second is her when she’s a little more than a year old. She still begs to be picked up like this every time I come home and when my arms get tired I lay her on her back and rub her stomach." – corys44c14457d

"The first photo was taken the day we met her, she was a 4 month old puppy and I was a freshman in high school and had just turned 15 a month ago. The second photo was taken a few weeks ago when I came home during a break from school: She’s 5 now and I’m almost 20. Time has flown by way too fast!" – giav41cc6e5b0

"She passed away July, 2017. First picture is spring, 2003; second is probably around 2005; third is summer, 2013; and the last is Christmas, 2016. Adopting her was one of my first memories. She was a QUEEN." – shannonw44e8d24aa

"I got him New Year's Eve, 2016, and we have been inseparable since. He was barely two months when I adopted him, and he took a liking to being on my shoulder, much like a pirate. Well, two years and a divorce later, not much has changed with him, he still likes to be the Parrot dog." – alexi4d55404d7

"My family got him in 2002, when I was 8 years old. The picture on the left is the two of us in 2004, and the photo on the right is from 2016. Sadly, Amos recently passed away in January at 15 years old. Rest in Peace, my sweet boy." – juliam43

36."Bungie my Siberian Husky. He was 10 weeks old in the top left picture, 8 months old in the top right picture, and 2 years old in the bottom pictures!"

"She is a Golden Retriever/Border Collie mix. She’s about three weeks old in the picture on the left and a little over a year old in the picture on the right. She was abandoned, so we got her at two weeks old and had to bottle feed her. She has been the biggest blessing in our lives. Nova is the weirdest, most loving pupper and we couldn’t imagine our lives without her weirdness." – samanthad41087efab

"Bentley has had health issues his entire life (allergies, tumours, etc.), but thankfully has managed to beat them all and has grown to be such an amazing dog.

"Recently, Bentley had to get emergency surgery which caused him to lose a lot of his mobility, but through physical therapy and a lot of courage he’s been able to slowly get back on his feet. I know that he doesn’t have much time left, but he lives each and every day with a smile and a spring in his step!

"Everyone I know can confirm that Bentley is the sweetest, kindest, calmest, and funniest Labradoodle there ever was, and he has been the absolute best friend in my life. I love him so much, and everyone in the world deserves to know who Bentley is and to know that he is the good-est boy there ever was." – emmaa42d476f63

Note: Submissions have been edited for length and/or clarity.

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